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Synonyms

overnight

American  
[oh-ver-nahyt, oh-ver-nahyt, oh-ver-nahyt] / ˈoʊ vərˈnaɪt, ˈoʊ vərˌnaɪt, ˌoʊ vərˈnaɪt /

adverb

  1. for or during the night.

    to stay overnight.

  2. on or during the previous evening.

    Preparations were made overnight.

  3. very quickly; suddenly.

    New suburbs sprang up overnight.


adjective

  1. done, made, occurring, or continuing during the night.

    an overnight stop; an overnight decision.

  2. staying for one night.

    a group of overnight guests.

  3. designed to be used on a trip or for a journey lasting one night or only a few nights.

  4. intended for delivery on the next day.

    overnight letters; an overnight package.

  5. valid for one night.

    The corporal got an overnight pass.

  6. occurring suddenly or within a very short time.

    a comedian who became an overnight sensation.

noun

  1. Informal. an overnight stay or trip.

    Our daughter had an overnight at a friend's house.

  2. Informal. a permit for overnight absence, as from a college dormitory.

    She had an overnight the night of the prom.

  3. the previous evening.

verb (used without object)

  1. to have an overnight stay or trip.

    We'll overnight in Denver, then fly on to San Diego.

overnight British  

adverb

  1. for the duration of the night

    we stopped overnight

  2. in or as if in the course of one night; suddenly

    the situation changed overnight

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adjective

  1. done in, occurring in, or lasting the night

    an overnight stop

  2. staying for one night

    overnight guests

  3. lasting one night

    an overnight trip

    an overnight bank loan

  4. for use during a single night

    overnight clothes

  5. occurring in or as if in the course of one night; sudden

    an overnight victory

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

verb

  1. to stay the night

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of overnight

Middle English word dating back to 1325–75; see origin at over-, night

Explanation

When something happens overnight, it occurs during the hours of one night. An overnight party can also be called a sleepover or a slumber party. (Pack your sleeping bag, but you probably won't use it.) You can use overnight as an adverb or adjective literally meaning "during the night" — like an overnight airplane flight or a guest who stays overnight on your couch. You can also use it figuratively, to mean "quickly" or "instant." After you publish your first book, you may be an overnight success; and after an important election, the world may seem to change overnight.

Keep Reading on Vocabulary.com

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The purpose of high-school sports changed overnight for many athletes and their families.

From The Wall Street Journal • May 10, 2026

That erosion of public trust did not emerge overnight.

From Salon • May 9, 2026

For most councils counting overnight, only a third of seats were up for election, so the party's best chance of winning power could be later in the day.

From BBC • May 8, 2026

Rescuers pulled his body from the water after half an hour and rushed him to Los Angeles General Medical Center, where Michelle works on the overnight cleaning crew.

From Los Angeles Times • May 8, 2026

The cold front rolls in overnight, just as the meteorologists predicted.

From "The Sea in Winter" by Christine Day